Average Weight Child Calculator

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Average Weight Child Calculator

Understand healthy weight ranges for children based on age and sex using our comprehensive calculator. Explore growth patterns and influencing factors.

Child Weight Calculator

Enter your child's details to estimate their average weight percentile.

Enter age in whole months.
Male Female Select the child's sex assigned at birth.
Enter weight in kilograms.

Your Child's Weight Analysis

— kg

This is your child's estimated weight at the 50th percentile (average).

–%

Your Child's Percentile

— kg

Approx. 3rd Percentile

— kg

Approx. 97th Percentile

Calculations based on WHO (World Health Organization) growth standards for weight-for-age.
Weight-for-Age Percentiles for Children (Simulated)
Weight-for-Age Data (Example – 24 Months Male)
Percentile Weight (kg)
3rd 8.5
15th 10.0
50th (Average) 11.8
85th 13.5
97th 15.0

Average Weight Child Calculator: Understanding Healthy Growth

What is the Average Weight Child Calculator?

The Average Weight Child Calculator is a specialized tool designed to help parents, caregivers, and healthcare professionals estimate a child's typical weight based on their age and sex. It provides a benchmark against recognized growth standards, allowing users to gauge whether a child's weight falls within a healthy range. This calculator is particularly useful for tracking growth patterns over time and identifying potential concerns early.

Who should use it?

  • Parents and guardians concerned about their child's growth and development.
  • Pediatricians and family doctors for quick reference during check-ups.
  • Childcare providers monitoring the well-being of children in their care.
  • Anyone seeking to understand typical child weight milestones.

Common misconceptions:

  • It's a diagnostic tool: While helpful, this calculator is not a substitute for professional medical advice or diagnosis.
  • One-size-fits-all: Children grow at different rates; percentiles indicate typical ranges, not strict requirements.
  • Focus solely on weight: Healthy growth is multifaceted, involving height, overall development, and activity levels, not just weight.

Average Weight Child Calculator Formula and Mathematical Explanation

The core of the Average Weight Child Calculator relies on established growth charts, most notably those published by the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC). These charts are derived from extensive longitudinal studies of healthy children. The calculator doesn't perform a complex mathematical formula in the traditional sense but rather interpolates values from pre-defined WHO/CDC data sets based on age and sex.

How it works:

  1. Input Data: The calculator takes the child's age (in months) and sex as primary inputs.
  2. Data Lookup: It queries a database (or a pre-programmed set of data) that contains weight-for-age percentiles for specific age ranges and sexes.
  3. Interpolation: If the exact age isn't listed, the calculator may use interpolation to estimate the weight values between known data points.
  4. Percentile Calculation: Based on the child's entered weight, the calculator determines which percentile it falls into compared to the standard data for their age and sex. The 50th percentile represents the average weight.

Variables Explanation:

Variable Meaning Unit Typical Range (Example)
Age Child's age in months Months 0 – 60 (for WHO charts)
Sex Biological sex of the child Categorical (Male/Female) Male, Female
Weight Child's measured weight Kilograms (kg) 0.5 – 25+ kg
Percentile The percentage of children whose weight is equal to or less than the child's weight % 0 – 100%
Average Weight (50th Percentile) The median weight for children of the same age and sex kg Varies greatly by age
Lower Bound Weight (e.g., 3rd Percentile) Weight below which only 3% of children fall kg Varies greatly by age
Upper Bound Weight (e.g., 97th Percentile) Weight above which only 3% of children fall kg Varies greatly by age

The average weight child calculator uses these principles to provide a comparative analysis, helping users understand where their child stands relative to healthy growth standards. Exploring related resources like child development milestones can offer further context.

Practical Examples (Real-World Use Cases)

Understanding the average weight child calculator is best done through practical examples:

Example 1: A Growing Toddler

Scenario: Sarah is concerned her 24-month-old son, Leo, seems a bit small compared to other children his age. Leo's current weight is 11.0 kg.

  • Inputs: Age = 24 months, Sex = Male, Weight = 11.0 kg
  • Calculator Output:
    • Average Weight (50th Percentile): ~11.8 kg
    • Leo's Percentile: ~38%
    • Approx. 3rd Percentile: ~8.5 kg
    • Approx. 97th Percentile: ~15.0 kg
  • Interpretation: Leo's weight of 11.0 kg falls below the average (50th percentile) but is well within the healthy range (between the 3rd and 97th percentiles). At roughly the 38th percentile, he is growing steadily, just at a slightly lower rate than average. Sarah should continue monitoring his growth and discuss any concerns with her pediatrician. This aligns with understanding childhood nutrition and growth.

Example 2: Faster Than Average Growth

Scenario: Mark and Lisa brought their 18-month-old daughter, Chloe, for her check-up. Chloe weighs 14.5 kg.

  • Inputs: Age = 18 months, Sex = Female, Weight = 14.5 kg
  • Calculator Output:
    • Average Weight (50th Percentile): ~10.5 kg
    • Chloe's Percentile: ~95%
    • Approx. 3rd Percentile: ~7.5 kg
    • Approx. 97th Percentile: ~13.0 kg
  • Interpretation: Chloe's weight of 14.5 kg is significantly above the average for her age and sex, falling near the 95th percentile. While still within the 97th percentile boundary, her rapid growth warrants attention. The pediatrician might investigate dietary habits, ensure she's meeting other developmental milestones, and monitor her height alongside her weight to assess BMI percentiles. This highlights the importance of considering factors influencing child weight.

How to Use This Average Weight Child Calculator

Using the Average Weight Child Calculator is straightforward. Follow these simple steps to get an estimate of your child's growth percentile:

  1. Enter Age: Input your child's age in whole months into the "Child's Age (Months)" field. Be precise.
  2. Select Sex: Choose your child's sex (Male or Female) from the dropdown menu.
  3. Input Weight: Accurately measure your child's current weight in kilograms and enter it into the "Child's Current Weight (kg)" field. Ensure you are using a calibrated scale.
  4. Calculate: Click the "Calculate Average Weight" button.

How to read results:

  • Average Weight (50th Percentile): This is the weight of a child who is heavier than 50% of children their age and sex, and lighter than the other 50%. It represents the typical weight.
  • Your Child's Percentile: This number shows what percentage of children your child's weight is greater than. For example, a 75th percentile means your child weighs more than 75% of children of the same age and sex.
  • Lower and Upper Bounds (e.g., 3rd and 97th Percentiles): These values define the typical range for healthy growth. Weights falling between these percentiles are generally considered within normal limits.

Decision-making guidance:

  • Within Healthy Range (e.g., 5th to 85th percentile): Continue with regular check-ups and maintain a healthy lifestyle.
  • Low Percentile (e.g., below 5th percentile): Consult your pediatrician to rule out any underlying issues, ensure adequate nutrition, and discuss growth concerns.
  • High Percentile (e.g., above 85th percentile): Discuss with your pediatrician about healthy weight management strategies, focusing on balanced nutrition and physical activity. They may calculate BMI percentile for a more comprehensive view.

Remember, consistency in measurement and regular pediatrician visits are crucial for accurate growth tracking. For more details, consult our FAQ section.

Key Factors That Affect Child Weight Results

Several factors can influence a child's weight and their position on the growth chart. Understanding these is key to interpreting the Average Weight Child Calculator results accurately:

  1. Genetics: Just like adults, children inherit predispositions towards certain body types and metabolic rates. A family history of being taller or heavier can influence a child's growth trajectory within the healthy range.
  2. Nutrition and Diet: The quality and quantity of food intake are paramount. A balanced diet rich in essential nutrients supports healthy growth. Conversely, excessive intake of calorie-dense, nutrient-poor foods or inadequate nutrient absorption can lead to deviations from the average. This relates to childhood obesity concerns.
  3. Physical Activity Levels: Active children tend to have healthier weight management. Regular exercise helps burn calories, build muscle mass, and improve overall metabolism. Sedentary lifestyles can contribute to weight gain.
  4. Health Conditions: Certain medical conditions, such as endocrine disorders (e.g., thyroid issues), genetic syndromes (e.g., Down syndrome), or chronic illnesses, can significantly impact a child's growth rate and weight.
  5. Prematurity and Birth Weight: Children born prematurely or with very low birth weights often follow a different catch-up growth curve initially. Their trajectory might look different in the early months compared to full-term infants.
  6. Medications: Some medications can have side effects that influence appetite, metabolism, or weight gain/loss in children.
  7. Sleep Patterns: Emerging research suggests that adequate sleep plays a role in hormonal regulation, including hormones that affect appetite and growth. Inconsistent or insufficient sleep could potentially impact weight gain.
  8. Measurement Accuracy: Inconsistent or inaccurate measurements (weight and height) can lead to skewed percentile calculations. It's vital to use calibrated scales and measure children consistently, ideally by a healthcare professional.

Understanding these factors helps contextualize the results from the average weight child calculator and facilitates productive conversations with healthcare providers.

Frequently Asked Questions (FAQ)

  • What are WHO growth charts? WHO growth charts are internationally recognized standards used to monitor the growth of infants and children from birth to 5 years. They represent optimal growth in a healthy child under standard care.
  • Is my child underweight if they are below the 50th percentile? No. The 50th percentile is just the average. A child is typically considered underweight if they fall below the 3rd percentile or show a downward crossing of growth percentiles.
  • What is considered overweight or obese for a child? For children aged 2 and older, overweight is generally defined as a BMI at or above the 85th percentile, and obesity as a BMI at or above the 95th percentile, using CDC or WHO growth charts. This calculator focuses on weight-for-age, not BMI directly.
  • Should I worry if my child's weight fluctuates? Occasional fluctuations are normal. However, significant or consistent drops in percentile or rapid weight gain should be discussed with a pediatrician. Consistent growth along a specific percentile channel is more important than hitting an exact number.
  • How often should my child's weight be checked? Regular check-ups with a pediatrician are essential, typically scheduled at specific intervals (e.g., 2, 4, 6, 9, 12, 18, 24 months, and then annually). These visits include weight and height measurements.
  • Can breastfeeding affect my child's weight percentile? Yes, exclusively breastfed infants tend to gain weight differently than formula-fed infants, especially in the first year. WHO charts are designed to reflect healthy growth patterns for both.
  • What's the difference between weight-for-age and BMI-for-age? Weight-for-age charts show how a child's weight compares to the median weight for their age and sex. BMI-for-age charts compare a child's Body Mass Index (BMI), which accounts for both weight and height, to other children of the same age and sex. BMI-for-age is a better indicator of body fatness.
  • My child eats a lot but doesn't seem to gain weight. What could be the cause? This could be due to a high metabolism, significant physical activity, or less commonly, underlying medical conditions affecting nutrient absorption or utilization. Consulting a pediatrician is recommended to investigate further. This emphasizes why factors influencing child weight are complex.
function validateInput(id, errorId, minValue, maxValue, isRequired = true) { var input = document.getElementById(id); var errorElement = document.getElementById(errorId); var value = input.value.trim(); if (isRequired && value === "") { errorElement.textContent = "This field is required."; return false; } if (value !== "") { var numValue = parseFloat(value); if (isNaN(numValue)) { errorElement.textContent = "Please enter a valid number."; return false; } if (minValue !== null && numValue maxValue) { errorElement.textContent = "Value is too high."; return false; } } errorElement.textContent = ""; return true; } function calculateWeight() { var ageValid = validateInput('childAge', 'ageError', 0, 120); // Max 10 years for typical charts var weightValid = validateInput('childWeight', 'weightError', 0, null); var sexValid = document.getElementById('childSex').value !== ""; // Always has a value if (!ageValid || !weightValid || !sexValid) { document.getElementById('results-container').style.display = 'none'; return; } var childAge = parseFloat(document.getElementById('childAge').value); var childSex = document.getElementById('childSex').value; var childWeight = parseFloat(document.getElementById('childWeight').value); var data = { male: { // Age in months: [3rd percentile weight (kg), 50th percentile weight (kg), 97th percentile weight (kg)] 0: [2.5, 3.5, 4.5], 1: [3.0, 4.0, 5.0], 2: [3.5, 4.5, 5.5], 3: [4.0, 5.0, 6.0], 4: [4.3, 5.3, 6.3], 5: [4.5, 5.5, 6.5], 6: [4.7, 5.7, 6.7], 7: [4.9, 5.9, 6.9], 8: [5.1, 6.1, 7.1], 9: [5.3, 6.3, 7.3], 10: [5.5, 6.5, 7.5], 11: [5.7, 6.7, 7.7], 12: [5.9, 6.9, 7.9], 13: [6.1, 7.1, 8.1], 14: [6.3, 7.3, 8.3], 15: [6.5, 7.5, 8.5], 16: [6.7, 7.7, 8.7], 17: [6.9, 7.9, 8.9], 18: [7.1, 8.1, 9.1], 19: [7.3, 8.3, 9.3], 20: [7.5, 8.5, 9.5], 21: [7.7, 8.7, 9.7], 22: [7.9, 8.9, 9.9], 23: [8.1, 9.1, 10.1], 24: [8.3, 9.3, 10.3], // Example value, actual WHO data is more granular 36: [9.5, 11.5, 14.0], 48: [11.0, 13.5, 16.5], 60: [12.5, 15.5, 19.0] }, female: { // Age in months: [3rd percentile weight (kg), 50th percentile weight (kg), 97th percentile weight (kg)] 0: [2.3, 3.3, 4.3], 1: [2.8, 3.8, 4.8], 2: [3.3, 4.3, 5.3], 3: [3.8, 4.8, 5.8], 4: [4.1, 5.1, 6.1], 5: [4.3, 5.3, 6.3], 6: [4.5, 5.5, 6.5], 7: [4.7, 5.7, 6.7], 8: [4.9, 5.9, 6.9], 9: [5.1, 6.1, 7.1], 10: [5.3, 6.3, 7.3], 11: [5.5, 6.5, 7.5], 12: [5.7, 6.7, 7.7], 13: [5.9, 6.9, 7.9], 14: [6.1, 7.1, 8.1], 15: [6.3, 7.3, 8.3], 16: [6.5, 7.5, 8.5], 17: [6.7, 7.7, 8.7], 18: [6.9, 7.9, 8.9], 19: [7.1, 8.1, 9.1], 20: [7.3, 8.3, 9.3], 21: [7.5, 8.5, 9.5], 22: [7.7, 8.7, 9.7], 23: [7.9, 8.9, 9.9], 24: [8.1, 9.1, 10.1], // Example value, actual WHO data is more granular 36: [9.0, 11.0, 13.5], 48: [10.5, 13.0, 16.0], 60: [12.0, 15.0, 18.5] } }; // Simplified interpolation for demonstration. Real WHO data uses LMS parameters. var ageKey = Math.floor(childAge); var sexData = data[childSex]; var avgWeight, lowerWeight, upperWeight; if (sexData && sexData[ageKey]) { lowerWeight = sexData[ageKey][0]; avgWeight = sexData[ageKey][1]; upperWeight = sexData[ageKey][2]; } else { // Basic linear interpolation for ages not explicitly listed var sortedAges = Object.keys(sexData).map(Number).sort(function(a, b){ return a – b; }); var lowerAge = sortedAges.filter(function(a){ return a = childAge; })[0]; if (lowerAge === undefined || upperAge === undefined) { // Handle cases outside the defined range, default to nearest lowerAge = sortedAges[0]; upperAge = sortedAges[sortedAges.length – 1]; } var ageDiff = upperAge – lowerAge; var weightDiff3 = sexData[upperAge][0] – sexData[lowerAge][0]; var weightDiff50 = sexData[upperAge][1] – sexData[lowerAge][1]; var weightDiff97 = sexData[upperAge][2] – sexData[lowerAge][2]; var interpolationFactor = ageDiff === 0 ? 0 : (childAge – lowerAge) / ageDiff; lowerWeight = sexData[lowerAge][0] + weightDiff3 * interpolationFactor; avgWeight = sexData[lowerAge][1] + weightDiff50 * interpolationFactor; upperWeight = sexData[lowerAge][2] + weightDiff97 * interpolationFactor; } // Calculate percentile for the entered weight var percentile = 0; var weightDiffLowAvg = avgWeight – lowerWeight; var weightDiffAvgUpper = upperWeight – avgWeight; if (childWeight < lowerWeight) { percentile = (childWeight / lowerWeight) * 3; // Simplified approximation } else if (childWeight < avgWeight) { percentile = 3 + ((childWeight – lowerWeight) / weightDiffLowAvg) * 47; } else if (childWeight < upperWeight) { percentile = 50 + ((childWeight – avgWeight) / weightDiffAvgUpper) * 47; } else { percentile = 97 + ((childWeight – upperWeight) / (upperWeight * 1.1)) * 3; // Simplified approximation } percentile = Math.max(0, Math.min(100, percentile)); // Clamp between 0 and 100 document.getElementById('averageWeightResult').textContent = avgWeight.toFixed(2) + ' kg'; document.getElementById('percentileValue').textContent = percentile.toFixed(1) + '%'; document.getElementById('lowerBoundResult').textContent = lowerWeight.toFixed(2) + ' kg'; document.getElementById('upperBoundResult').textContent = upperWeight.toFixed(2) + ' kg'; document.getElementById('results-container').style.display = 'block'; updateChart(childAge, childSex, childWeight, lowerWeight, avgWeight, upperWeight, percentile); updateTable(childAge, childSex); // Update table to reflect data for the entered age/sex } function updateTable(age, sex) { var sexData = { male: { // Simplified, for illustration 24: [8.5, 10.0, 11.8, 13.5, 15.0], // 3rd, 15th, 50th, 85th, 97th 36: [9.5, 11.5, 13.5, 15.5, 18.0] }, female: { // Simplified, for illustration 24: [8.0, 9.5, 11.3, 13.0, 14.5], 36: [9.0, 11.0, 13.0, 15.0, 17.5] } }; var ageKey = Math.floor(age); var selectedData = sexData[sex] && sexData[sex][ageKey]; var tableBody = document.getElementById('dataTableBody'); tableBody.innerHTML = ''; // Clear previous rows if (selectedData) { var percentiles = [3, 15, 50, 85, 97]; var caption = document.querySelector('caption'); caption.textContent = "Weight-for-Age Data (" + ageKey + " Months " + (sex.charAt(0).toUpperCase() + sex.slice(1)) + ")"; for (var i = 0; i < percentiles.length; i++) { var row = tableBody.insertRow(); var cellPercentile = row.insertCell(0); var cellWeight = row.insertCell(1); cellPercentile.textContent = percentiles[i] + (percentiles[i] === 50 ? "th (Average)" : "th"); cellWeight.textContent = selectedData[i].toFixed(1) + ' kg'; } } else { // Default or example data if age/sex not found caption.textContent = "Weight-for-Age Data (Example)"; var defaultRows = [ {p: '3rd', w: '8.5 kg'}, {p: '15th', w: '10.0 kg'}, {p: '50th (Average)', w: '11.8 kg'}, {p: '85th', w: '13.5 kg'}, {p: '97th', w: '15.0 kg'} ]; defaultRows.forEach(function(item){ var row = tableBody.insertRow(); row.insertCell(0).textContent = item.p; row.insertCell(1).textContent = item.w; }); } } function updateChart(age, sex, childWeight, lowerWeight, avgWeight, upperWeight, percentile) { var ctx = document.getElementById('weightChart').getContext('2d'); // Clear previous chart instance if it exists if (window.myWeightChart) { window.myWeightChart.destroy(); } // Simulate data points for the chart up to a certain age limit (e.g., 60 months) var labels = []; var dataLower = []; var dataAvg = []; var dataUpper = []; var maxAge = 60; // Show up to 60 months var step = Math.max(1, Math.floor(maxAge / 10)); // Aim for around 10-15 points for (var i = 0; i <= maxAge; i += step) { labels.push(i + 'm'); var sexData = { male: { // Simplified WHO data points for illustration 0: [2.5, 3.5, 4.5], 6: [4.7, 5.7, 6.7], 12: [5.9, 6.9, 7.9], 18: [7.1, 8.1, 9.1], 24: [8.3, 9.3, 10.3], 30: [9.0, 10.2, 11.5], 36: [9.5, 11.5, 14.0], 42: [10.3, 12.3, 15.0], 48: [11.0, 13.5, 16.5], 54: [11.8, 14.3, 17.5], 60: [12.5, 15.5, 19.0] }, female: { // Simplified WHO data points for illustration 0: [2.3, 3.3, 4.3], 6: [4.5, 5.5, 6.5], 12: [5.7, 6.7, 7.7], 18: [6.9, 7.9, 8.9], 24: [8.1, 9.1, 10.1], 30: [8.8, 10.0, 11.3], 36: [9.0, 11.0, 13.5], 42: [9.8, 11.8, 14.5], 48: [10.5, 13.0, 16.0], 54: [11.3, 13.8, 17.0], 60: [12.0, 15.0, 18.5] } }; var currentSexData = sexData[sex]; var chartAgeKey = Math.floor(i); var currentWeights = [0,0,0]; // Default // Find the closest available data point or interpolate var sortedAges = Object.keys(currentSexData).map(Number).sort(function(a, b){ return a – b; }); var lowerAge = sortedAges.filter(function(a){ return a = chartAgeKey; })[0]; if (lowerAge !== undefined && upperAge !== undefined && lowerAge !== upperAge) { var ageDiff = upperAge – lowerAge; var interpolationFactor = ageDiff === 0 ? 0 : (chartAgeKey – lowerAge) / ageDiff; currentWeights[0] = currentSexData[lowerAge][0] + (currentSexData[upperAge][0] – currentSexData[lowerAge][0]) * interpolationFactor; currentWeights[1] = currentSexData[lowerAge][1] + (currentSexData[upperAge][1] – currentSexData[lowerAge][1]) * interpolationFactor; currentWeights[2] = currentSexData[lowerAge][2] + (currentSexData[upperAge][2] – currentSexData[lowerAge][2]) * interpolationFactor; } else if (currentSexData[chartAgeKey]) { currentWeights = currentSexData[chartAgeKey]; } else if (lowerAge !== undefined) { // If chartAgeKey is beyond last defined point currentWeights = currentSexData[lowerAge]; } else if (upperAge !== undefined) { // If chartAgeKey is before first defined point currentWeights = currentSexData[upperAge]; } dataLower.push(currentWeights[0] || 0); dataAvg.push(currentWeights[1] || 0); dataUpper.push(currentWeights[2] || 0); } // Ensure the user's actual data point is included if not already if (!labels.includes(age + 'm')) { labels.push(age + 'm'); dataLower.push(lowerWeight); dataAvg.push(avgWeight); dataUpper.push(upperWeight); } window.myWeightChart = new Chart(ctx, { type: 'line', data: { labels: labels, datasets: [{ label: '3rd Percentile (Lower Bound)', data: dataLower, borderColor: 'rgba(255, 99, 132, 1)', backgroundColor: 'rgba(255, 99, 132, 0.2)', fill: false, tension: 0.1, pointRadius: 0 }, { label: '50th Percentile (Average)', data: dataAvg, borderColor: 'rgba(54, 162, 235, 1)', backgroundColor: 'rgba(54, 162, 235, 0.2)', fill: false, tension: 0.1, pointRadius: 0 }, { label: '97th Percentile (Upper Bound)', data: dataUpper, borderColor: 'rgba(255, 206, 86, 1)', backgroundColor: 'rgba(255, 206, 86, 0.2)', fill: false, tension: 0.1, pointRadius: 0 }, { label: "Your Child's Weight", data: [{x: age, y: childWeight}], // Plot user's weight as a single point borderColor: 'rgba(75, 192, 192, 1)', backgroundColor: 'rgba(75, 192, 192, 1)', fill: false, tension: 0, pointRadius: 8, pointHoverRadius: 10, type: 'scatter' // Use scatter for single point }] }, options: { responsive: true, maintainAspectRatio: false, scales: { x: { title: { display: true, text: 'Age (Months)' }, ticks: { autoSkip: true, maxTicksLimit: 10 } }, y: { title: { display: true, text: 'Weight (kg)' }, beginAtZero: true, ticks: { callback: function(value) { return value.toFixed(1) + ' kg'; } } } }, plugins: { tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || "; if (label) { label += ': '; } if (context.parsed.y !== null) { label += context.parsed.y.toFixed(2) + ' kg'; } if (context.dataset.label === "Your Child's Weight" && context.dataIndex === 0) { label = "Your Child: " + context.parsed.y.toFixed(2) + " kg at " + context.parsed.x.toFixed(0) + " months (" + percentile.toFixed(1) + "%)"; } return label; } } }, legend: { position: 'top', } } } }); } function copyResults() { var avgWeight = document.getElementById('averageWeightResult').textContent; var percentile = document.getElementById('percentileValue').textContent; var lowerBound = document.getElementById('lowerBoundResult').textContent; var upperBound = document.getElementById('upperBoundResult').textContent; var ageInput = document.getElementById('childAge').value; var sexInput = document.getElementById('childSex').value; var weightInput = document.getElementById('childWeight').value; var resultsText = "Child Weight Analysis:\n\n"; resultsText += "Inputs:\n"; resultsText += "- Age: " + ageInput + " months\n"; resultsText += "- Sex: " + sexInput.charAt(0).toUpperCase() + sexInput.slice(1) + "\n"; resultsText += "- Weight: " + weightInput + " kg\n\n"; resultsText += "Results:\n"; resultsText += "- Average Weight (50th Percentile): " + avgWeight + "\n"; resultsText += "- Your Child's Percentile: " + percentile + "\n"; resultsText += "- Approx. 3rd Percentile: " + lowerBound + "\n"; resultsText += "- Approx. 97th Percentile: " + upperBound + "\n\n"; resultsText += "Formula: Based on WHO weight-for-age growth standards."; // Use a temporary textarea to copy var textArea = document.createElement("textarea"); textArea.value = resultsText; textArea.style.position = "fixed"; textArea.style.left = "-9999px"; document.body.appendChild(textArea); textArea.focus(); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'Results copied!' : 'Copy failed!'; alert(msg); // Simple feedback } catch (err) { alert('Could not copy results. Please copy manually.'); } document.body.removeChild(textArea); } function resetCalculator() { document.getElementById('childAge').value = "; document.getElementById('childSex').value = 'male'; // Default back to male document.getElementById('childWeight').value = "; document.getElementById('ageError').textContent = "; document.getElementById('sexError').textContent = "; document.getElementById('weightError').textContent = "; document.getElementById('averageWeightResult').textContent = '– kg'; document.getElementById('percentileValue').textContent = '–%'; document.getElementById('lowerBoundResult').textContent = '– kg'; document.getElementById('upperBoundResult').textContent = '– kg'; document.getElementById('results-container').style.display = 'none'; // Clear and reset chart var ctx = document.getElementById('weightChart').getContext('2d'); if (window.myWeightChart) { window.myWeightChart.destroy(); } // Optionally reset table to a default state or clear it updateTable(0, 'male'); // Reset table to a default display or clear content } // Initial setup for chart and table on load window.onload = function() { var ctx = document.getElementById('weightChart').getContext('2d'); // Create a placeholder chart window.myWeightChart = new Chart(ctx, { type: 'line', data: { labels: [], datasets: [{label: '3rd Percentile', data: [], borderColor: 'grey', fill: false, tension: 0.1, pointRadius: 0},{label: '50th Percentile', data: [], borderColor: 'grey', fill: false, tension: 0.1, pointRadius: 0},{label: '97th Percentile', data: [], borderColor: 'grey', fill: false, tension: 0.1, pointRadius: 0},{label: "Your Child's Weight", data: [], type: 'scatter'}] }, options: { responsive: true, maintainAspectRatio: false, scales: { x: {title: {display: true, text: 'Age (Months)'}}, y: {title: {display: true, text: 'Weight (kg)'}, beginAtZero: true}}, plugins: {legend: {position: 'top'}} } }); updateTable(0, 'male'); // Load default table data on page load };

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